This invention relates in general to modular electrical wiring systems for commercial and industrial applications and deals more specifically with an improved pre-wired circuit component for a modular flexible wiring system particularly suitable for lighting applications.
Modular flexible wiring systems for the distribution of power to lighting fixtures used in office buildings, factories and the like, are known in the art and examples of such systems are found in U.S. Pat. No. 4,399,371 to Ziff et al. for Modular Wiring Systems, issued Aug. 16, 1983, and assigned to the assignee of the present invention. The pre-wired circuit component of the present invention is adapted for use in a flexible wiring system designed particularly to facilitate the installation of High Intensity Discharge (HID) commercial and industrial lightening fixtures with light sources such as mercury vapor, multi-vapor and high pressure sodium lamps which operate at differing voltages.
The general aim of the present invention is to provide an improved pre-wired circuit module to enable the provision of a system which utilizes a minimum number of components, satisfies a wide variety of applications, and gives the installer of HID commercial and industrial lightening fixtures a wide range of choices in the selection of fixtures for lighting applications. A further aim of the invention is to provide an improved pre-wired circuit component which includes a rotational circuit selector and an easy to read or feel circuit identifier which allows a qualified installer to select a phasing position at a fixture location during fixture installation. Yet another aim of the invention is to provide an improved pre-wired circuit component which includes integrated cable/cord clamping with internal strain relief.
Further objects and advantages of the invention will be apparent from the illustrations and description which follows.
In accordance with the present invention, a pre-wired circuit component for use in a flexible wiring system includes a housing defining a chamber containing a plurality of power conductors. An elongated flexible power supply cable for connection to a power supply source has at least three supply conductors and extends into the housing. Each of the supply conductors is connected to a respectively associated one of the power conductors within the housing. A rotational circuit selector assembly, which includes a generally cylindrical first connecting element, is mounted in fixed position in a power outlet opening in the housing and carries a first group of electrical contacts electrically connected to the power conductors within the housing. The rotational circuit selector further includes a generally cylindrical second connecting element for mating connection with the first connecting element. The second connecting element has a second group of electrical contacts which mate with contacts of the first group when the second connecting element is connected to the first connecting element. An elongated flexible cord drop attached to the second connecting element has a plurality of power outlet conductors, each electrically connected to a respectively associated one of the contacts of the second group. The cylindrical second connecting element is connectable in coaxial alignment to the first connecting element in a selected one of a plurality of possible connected positions angularly spaced from each other about the axis of the cylindrical first connecting element to establish electrical connection between electrical conductors in the supply cable and the cord drop. A pair of electrical outlet conductors of the cord drop are electrically connected to a different pair of electrical supply conductors of the supply cable in each one of the connected positions, whereby electrical power may be delivered by the supply cable to the cord drop at a substantially different voltage at each one of the possible connected positions.